AUSTRALIA'S leading mining companies are set for a wave of profit upgrades with bullish analysts factoring higher iron ore prices into earnings forecasts as China's economic recovery gathers pace.

BHP Billiton, Rio Tinto and Fortescue Metals are due to report in the next two weeks and Commonwealth Bank and UBS analysts have highlighted the upside to earnings if iron ore prices remain above $US150 a tonne.

Iron ore has jumped almost 80 per cent since hitting a low in September of $US87 a tonne. If those prices are sustained through the March quarter, CBA estimated Fortescue earnings would increase by 30 per cent, Rio's 12 per cent and BHP's 7 per cent. If sustained until June, Fortescue's earnings would jump 52 per cent, Rio's 22 per cent and BHP's 12 per cent.

''We could be on the verge of the first earnings upgrade for 18 months,'' wrote CBA's analysts. ''We are at the end of the downgrade cycle and the market should again begin focusing on the valuation upside.''

Earlier in the week, UBS calculated BHP and Rio earnings for 2013 would jump 22 per cent and 23 per cent respectively, while Fortescue's earnings would jump 54 per cent, if spot iron ore prices were sustained.

Rio is expected to report underlying earnings of $US9.1 billion for calendar 2012 on Thursday, although $US14 billion in impairments - which led to the shock resignation of former chief Tom Albanese last month - will tip the company to report its first-ever bottom line loss. BHP is expected to report underlying earnings of $US9.5 billion for its December half.

Higher profits should translate into higher mining tax revenues. Releasing figures on the $126 million paid in minerals resource rent tax in the first half of 2012-13, Treasurer Wayne Swan said concerns last year about Chinese economic weakness were ''overdone''.

He said there had been a recovery in commodity prices from the lows of last year, which had contributed to significantly higher MRRT payments in the December quarter than in September, as company profits rose.

''We have seen a partial recovery in profits,'' Mr Swan said. ''We will have to see how prices go over the next six months.''

The Reserve Bank's monetary policy statement on Friday said the latest bounce in commodity prices was likely to give national income a boost this year, but it forecast falls in exports over the longer term.

Recent price rises, the bank said, had ''coincided with increased industrial production in China and elsewhere in the region, although expectations are that iron ore prices will not be sustained at current high levels''.

None of the major mining companies that were party to the design of the MRRT - BHP, Rio or Xstrata - would confirm whether they had paid any MRRT in the first six months.

The Reserve also predicted coal demand would increase as the global economy recovered, but did not say what this meant for export prices.

At its recent December quarterly production update Fortescue chief financial officer Stephen Pearce told analysts: ''We do not pay and don't anticipate paying any MRRT. It's structured as a super profits tax, and at the moment the industry is not making super profits.''